How polar is your Food?

Pre Lab
When you read a chromatography paper how do you determine their relative polarity?


What is the most dangerous material we are working with today? And describe the best way to handle it.

Make a prediction on which dye is most polar.



Materials
  • Pencil
  • Paper
  • Ruler
  • Scissors
  • Toothpicks
  • 4 different food colors
  • Plastic cup
  • 0.1% NaCl solution (solvent)
  • Chromatography Paper
Procedure
1. Cut a 5x10 cm strip of chromatography paper label it with a pencil as shown below
2. Use a different toothpick to put a spot of each of the food dyes on the label on the X’s
3. Allow dots to dry for a few minutes
4. While they dry fill a plastic cup or beaker with just enough solvent to coat the bottom
5.
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    https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcSc9kkO484u3YB02YleAdyZbo_3bZJ8gbY2ettdAxQpD__mGGV9
    Put the paper in the solvent and wait till the solvent climes to the top of the paper and then let it dry.





Data Collection
Draw the chromatography paper and measure the spot distance for each and record distances.
Analysis
  1. 1. If the element is pure it will have a single spot which is pure?




2. Which are mixtures?




3. Food colors consists of more than one dye normally, look at the package and try and figure out what mixtures your dyes have.




4. Based on what I told you about polarity and which is most polar? And does it parallel your prediction?



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